Specifications
I/O Expansion Module Errors Appendix A: Troubleshooting
108 VisiLogic: Getting Started
I/O Expansion Module Errors
An interruption in communication between an I/O expansion module and
controller can cause the controller to enter Stop Mode, and an ‘Expansion
Error’ message to be displayed on the controller’s LCD.
This error results when:
1. The module was connected at power-up.
2. The communication between module and controller was interrupted for
more than 200 milliseconds. Interruptions may occur if the connecting
cables are disconnected, or may result from signal interference (noise).
Note
•
When a controller enters stop mode, the program stops running and
all outputs within the system are initialized. This includes on-board
outputs, outputs located on Snap-in I/O modules, and outputs located
I/O expansion modules.
What to do
Check that the cables are connected and in proper order.
Remedy signal interference. Such an error may also result from a
hardware malfunction.
If the RUN LED on the expansion module blinks, check the documentation
supplied with the expansion module to see if a hardware error is indicated.
To exit Stop Mode, reset the controller either by turning it off and on, or
by entering Information Mode, and then selecting System>Working
Mode> Reset.
Analog Input Values: Out of Range
Expansion modules
If an expansion module's analog input is receiving current or voltage in excess
of the absolute maximum rating, the corresponding Out Of Range indicator
lights up.
IO-AI4-AO2
Analog value: from 0 to 4095 (12 bit). If the analog input is:
below 0V/0mA, then the analog value will be 0.
above 10V/20mA (about 2% above the full scale), then the analog value
will be 4096.
IO-ATC8
Analog value: from 0 to 16383 (14 bit). If the analog input is:
slightly below 0V/0mA (about 0.5% below 0V/0mA), then the analog
value will be -1.
slightly above 10V/20mA (about 0.5% above the full scale), then the
analog value will be 16384.
If the analog input is greatly below or above of the analog input range
,but still within the range of the absolute maximum rating, then the
analog value will be 32767.